121856859 has 16 divisors (see below), whose sum is σ = 180835200. Its totient is φ = 81100008.

The previous prime is 121856857. The next prime is 121856863. The reversal of 121856859 is 958658121.

It is a happy number.

It is not a de Polignac number, because 121856859 - 2¹ = 121856857 is a prime.

It is a super-3 number, since 3×121856859³ (a number of 25 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (121856851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13852 + ... + 20870.

It is an arithmetic number, because the mean of its divisors is an integer number (11302200).

Almost surely, 2^121856859 is an apocalyptic number.

121856859 is a deficient number, since it is larger than the sum of its proper divisors (58978341).

121856859 is an equidigital number, since it uses as much as digits as its factorization.

121856859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7671 (or 7665 counting only the distinct ones).

The product of its digits is 172800, while the sum is 45.

The square root of 121856859 is about 11038.8794268259. The cubic root of 121856859 is about 495.7735197266.

It can be divided in two parts, 12185 and 6859, that added together give a square (19044 = 138²).

The spelling of 121856859 in words is "one hundred twenty-one million, eight hundred fifty-six thousand, eight hundred fifty-nine".